Radiation detection systems are currently being deployed throughout the world to help prevent catastrophic events. Some radiation detection systems utilize radiation directional detectors that try to identify the direction in which radiation is being emanated. Current radiation directional detectors use heavy shielding behind each detector to focus the detection in a specific direction. Other systems also deploy collimators to assist in directional detection. One type of radiation detector is a plastic scintillator, which has a low cost. Plastic scintillators can provide very large surface areas, which with optimal width is good for long distance detection. However, plastic scintillators do not have the ability to perform spectral analysis. Therefore, system based on plastic scintillators generally cannot identify the source of radiation, which can be naturally occurring radiation material (NORM).
Most current directional detector systems employ heavy metals for shielding that are in addition to the overall weight and cost. Another radiation detection method is to combine multiple detectors to define the vector of the photon. This method requires more than two detectors per direction to identify the photon vector. Another recent design uses four Cerium Doped Lanthanum Bromide (LaBr3:Ce) Scintillation detectors with high resolution capabilities to determine the vector of the radiation source. These specialized detectors are extremely expensive with crystals that cannot be grown to accommodate large surface area detectors. The Labr3:Ce scintillators have very strong identification capabilities, due to high resolution of Labr3:Ce detectors, but the high cost and limits in available detector crystal sizes makes them unpractical to use. Labr3:Ce scintillators have 180 degree symmetry. This means that Labr3:Ce scintillators cannot identify difference between a source in front of detector or with a same angle behind the detector.
The deficiencies of the current systems available do not address the needs of critical security applications. The current methods for creating directional radiation detectors are too costly, bulky or have heavy weight factors. In addition, the current radiation detection methods do not offer a combined stand-off detection, directional finder, position locator, radiation source movement tracking and isotope identification in a cost effective, light weight, and efficient approach that does not require highly specialized detector performance characteristics.
Therefore a need exists to overcome these problems as discussed above